JPS63178043A - Three layer tile and manufacture thereof - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Field of Application in Business A] The present invention relates to a three-layer tile and a method for manufacturing the same, and in particular, a three-layer tile and a method for manufacturing the same that eliminates the occurrence of tile warpage that is characteristic of two-layer tiles. Regarding.

[Prior art] Tiles are usually made from feldspar, clay, pottery stone, etc., which are ground and mixed, which are further ground into a slurry, which is dehydrated and dried, and which is then ground again. It is manufactured by putting the clay into a mold, dry-pressing it, drying it, and firing it.

Conventionally, in manufacturing tiles, a single-layer molding method has been adopted in which one type of clay is press-formed in the steps shown in FIGS. 2(a) to 2(f). In addition, in FIG. 2, (a) to (C) are cross-sectional views, and (d) to (f) are plan views. First, using the upper mold 1, frame 2a and lower mold 2 as shown in Fig. 2(a), move the clay container 3 (Fig. 2(d)
), (e)) Insert the embroidery ±3a into the area surrounded by the lower mold 2 and the frame 2a (same (b)), and after putting in the embroidery ±3a, return the embroidery inlet/output 3 to its original position. (f)) Next, the upper mold 1 is lowered and dry press molding is performed. (same (C)).

However, the single-layer tile obtained by such a single-layer method requires the following: In order to color the molded product, pigment must be added not only to the surface of the molded product but also to the entire surface of the molded product, which consumes a large amount of pigment. Material costs are high.

■ If the clay contains easily meltable substances such as iron compounds, they will adhere to refractory materials such as pots, shelves, or rollers during the firing process, causing product defects and deterioration of the refractory materials.

■ It is difficult to provide different functions inside the tiles.

It had the following drawbacks.

Therefore, in recent years, as shown in Figures 3 (a) to (j), two
A two-layer molding method in which ffl-type clay is added and press-molded has come to be adopted.

Note that FIGS. 3(a) to 3(e) are cross-sectional views, and FIGS. 3(f) to (j)
is a plan view. This method consists of an upper mold 1, a lower mold 2, a frame 2a, and two clay containers 3.4 as shown in FIGS. 3(a) and 3(f).
Molding is performed using 2 ffl type molding tools ±3a and 4a.

First, put the clay material ±38 into the lower mold using the clay container 3 (same (b)
), (g), (h)) After that, lower the bottom side of the lower mold 2 (same as (C)), and then put the clay 4a into the lower mold 2 using the clay container 4 (same as that). (i), (d), (j), lower the upper die 1 and perform dry press molding ((e)).

Two-layer tiles obtained by such a two-layer molding method are: ■ If coloring is required, pigments need only be added to the layer on the surface side of the tile, which reduces the amount of pigment required and reduces material costs. .

■ As raw clay, clay with the desired quality such as color and surface shape can be used only for the front layer of the tile, and low-quality materials such as waste mud can be used for the back layer. ,
Cost reduction can be achieved.

■ Even if clay with the desired quality contains substances that easily melt during firing, such as iron compounds, by using clay that does not contain such substances as the lower layer, This prevents the fired product from adhering to the refractory material (for example, the roller of a roller hearth kiln) during the firing process, thereby preventing product defects and deterioration of the refractory material.

■ Even substances that cannot be molded alone, such as non-plastic materials, can be molded by combining them with other clays that can exhibit high strength.

It has the following advantages.

[Problems to be Solved by the Invention] As described above, while the two-layer tile has excellent advantages, it also has the following drawbacks.

In other words, in the case of a two-layer tile, if there is a difference in the shrinkage rate between the upper layer clay and the lower layer clay during drying and firing (i.e., the shrinkage rate during the temperature rise process of firing and the sintering in the firing zone after the temperature rise). (if there is a clear difference in the amount of shrinkage between the If there is a clear difference in the amount of shrinkage caused by a difference in the coefficient of thermal expansion of the lower layer), deformation such as warping occurs in the tile, and if the deformation becomes large, the upper layer and the lower layer may separate.

This problem does not occur if there is no difference in the coefficient of thermal expansion or contraction between the upper layer clay and the lower layer clay, but in most cases there is a considerable difference, so two layers The problem of tile warping could not be avoided. Warpage is particularly noticeable in large tiles with sides of 300 mm or more.

[Means for solving the problem] The three-layer tile of the present invention has a three-layer structure in which the first layer, the second layer, and the third layer are laminated in this order, and the first layer and the third layer are The shrinkage rate during drying and firing and the thermal expansion coefficient of the sintered base material are approximately similar, and the third layer contains high refractory grains.

In addition, the method for producing a three-layer tile of the present invention is to fill a tile molding mold with clay as a raw material for tiles to form a third layer, and fill the third layer with clay different from the clay of the third layer. and make it the second layer,
Next, on the second layer, a clay having a shrinkage rate during drying and firing and a coefficient of thermal expansion of the sintered base material that are approximately similar to the clay of the third layer and containing high refractory grains is filled. as the first layer,
This is characterized by dry press molding and then firing.

The present invention will be explained in detail below with reference to the drawings.

As shown in FIG. 1, the three-layer tile 10 of the present invention is made up of a first layer 11, a second layer 12, and a third layer 13 stacked one after another.

In the tiles of the present invention, in order to reliably prevent the tiles from warping, the clay used for the first layer and the clay used for the third layer have different shrinkage rates during drying and firing, and the sintered base (
The thermal expansion coefficients of the base material sintered in the firing zone are approximately similar. The shrinkage rate A of the clay used for the first layer and the shrinkage rate C of the clay used for the third layer are respectively 0.8C<A<1.2C 0.6B< A, C<1.4B especially 0.9C<A<1. It is preferable that IC 0,8B<A and C<1.2B.

If the shrinkage rate during drying and firing and the thermal expansion coefficient of the fired base material between the first layer and the second layer or between the second layer and the third layer are significantly different, warping will not occur but the surface of the first or third layer will not warp. Penetrating defects and peeling may occur within each layer, between the first layer and the second layer, or between the second layer and the third layer.

In the present invention, the first layer of clay may be ordinary tile raw materials such as feldspar, pottery stone, and clay, but in addition to these, low-refractory particles such as coarse feldspar, metal slag, and iron compounds may be used. It is extremely preferable to use a compound containing . Since these low refractory grains easily melt during firing, a stone-like or astronomical pattern appears on the tile surface.

Further, in the present invention, as the third layer, for example, a material obtained by adding high refractory grains such as chamotte and chinastone grains to ordinary tile raw material clay is used. By including this high refractory grain, when fired with the third layer facing down,
This third layer is prevented from adhering to the refractory material (for example, the rollers of a roller hearth kiln) of a firing furnace (for example, a roller hearth kiln or a tunnel kiln). Note that the above-mentioned low refractory grains that are sometimes added to the first layer are not added to this third layer.

In the present invention, it is suitable to use, for example, the following clay as the first layer, second layer, and third layer, but of course the present invention may use clay other than the following.

Example 1 First layer feldspar 40-80 parts by weight porcelain stone
0 to 40 parts by weight Clay 5 to 40 parts by weight Sand and/or feldspar grains 0 to 80 parts by weight (The sand is preferably washed mountain sand, sea sand, or river sand.) Second layer feldspar 20-60 parts by weight Ceramic stone
0 to 40 parts by weight Clay 20 to 60 parts by weight Chamotte 0 to 25 parts by weight (for example, crushed tiles made by mixing and firing 30 parts by weight of feldspar, 50 parts by weight of clay, and 20 parts by weight of chinastone) Third layer length Stone 40-80 parts by weight Ceramic stone
0 to 40 parts by weight Clay 5 to 40 parts by weight Chamotte 0 to 80 parts by weight (same chamotte as above) Example 2 First layer Feldspar 20 to 70 parts by weight Ceramic stone
30-80 parts by weight Clay O-20 parts by weight Sand and/or feldspar grains 0-70 parts by weight Second layer Same as Example 1.

third layer Same as example 1.

Example 3 First layer feldspar 40-80 parts by weight porcelain stone
0 to 40 parts by weight Clay 5 to 40 parts by weight Sand and/or feldspar grains 0 to 80 parts by weight Spots 10 to 150 parts by weight (spots are made by adding pigments to the above proportions of feldspar, chinastone and clay. This was pressed, dried, crushed, and sieved to about 4 to 8 meshes.) Second layer: Same as Example 1.

third layer Same as example 1.

The thickness of each of the first to third layers varies depending on the size and thickness of the tile 10, but when the first layer 11 is on the front side of the tile, the thickness of the first layer should be 2 mm or more. preferable. If the thickness of the first layer is less than 2 mm, if low-grade clay is used for the second layer, the second layer will affect the tile surface, causing uneven coloring, unevenness, etc. This can lead to product defects. The third layer is a layer to prevent the tile from warping during the firing process, etc., and when placed on the back side of the finished tile, it should be coated with a layer that is strong enough to cover the uneven color and unevenness caused by the second layer, like the first layer. Although the thickness is not particularly required, it is preferable that the first and third layers have approximately the same thickness. There is no particular limit to the thickness of the second layer, but if ordinary tile raw material clay is used for the first and third layers and low-grade raw material clay such as industrial waste is used for the second layer. As the thickness of the second layer becomes relatively larger, more low-grade raw materials can be used, which is advantageous in terms of cost reduction and reuse of industrial waste.

Next, a method for manufacturing a three-layer tile according to the present invention will be explained.

FIGS. 4(a) to 4(n) are diagrams explaining the forming process of the three-layer tile of the present invention, and FIGS. 4(a) to 4(g) are cross-sectional views,
FIGS. 4(h) to 4(n) show plan views.

In the method for manufacturing a three-layer tile of the present invention, FIG.
) A mold consisting of an upper mold 1, a frame 2a, and a lower mold 2, and three types of raw materials ±3a, 4a, and 5a are prepared, and each of them is placed in a clay container as shown in (h) above. Fill to 5.

First, the clay container 3 is moved six times and the clay material ±38 is put into the lower mold 2 ((i), (b), (j)).

Next, lower the bottom part of the lower mold 2 (see (e)), and place the clay container 4.
6 times and put the clay 4a into the lower mold 2 (same (k)
, (d), (β)). Lower the bottom of the lower mold 2 again (same as (
e)), the clay container 5 is moved 8 times to put the clay material ±5a into the lower mold 2 ((m), (f), (n)). Finally, upper mold 1
is lowered and dry pressed ((g)).

In the illustrated method, the input amount of 坏±3a, 4a, 5a,
That is, the thickness of each layer of the resulting three-layer tile can be easily adjusted by adjusting the degree of lowering of the bottom surface of the lower mold 2.

In addition, in the method of the present invention, the method of dry press molding is not limited to that shown in FIGS. It can be done.

The molded product dry press-molded by the method shown in FIGS. 4(a) to (n) is one in which the first to third layers are integrally molded, and the molded product is molded in a roller hearth kiln according to the usual method. The three-layer tile of the present invention can be obtained by firing the tile in a firing furnace such as a tunnel kiln or the like.

[Function] In the three-layer tile of the present invention, since the shrinkage rates of the first layer and the third layer are similar, Warpage is prevented from occurring. Further, since the third layer contains high refractory grains, by firing with the third layer facing down, it is possible to prevent welding to a refractory (for example, a roller) during firing.

[Example] Examples will be described below.

Example 1 A three-layer tile molded body as shown in FIG. 1 was manufactured by the method shown in FIGS. 4(a) to 4(n).

The clay of the first layer, second layer, and third layer and the thickness of each layer are
The molding pressure of the dry press is approximately 350 kg as shown in the table.
/crn', the size of the molded body is 450mm x 450m
m x 20 mm (thickness), maximum 121 mm in tunnel kiln
A three-layer tile was produced by firing at 0° C. for about 50 hours from inlet to outlet, or at a maximum of 1310° C. for about 3 hr in an RHK (roller hearth kiln). The obtained three-layer tile was a one-piece product, and was in extremely good condition, with no defects such as color unevenness or unevenness. In addition, the sand in the first layer melted and appeared in the form of black spots, and the entire surface had an extremely beautiful surface pattern that resembled a natural stone surface.

The sand used in this example was obtained by washing and classifying (8 mesh under) mountain sand from the Seto region of Aichi Prefecture. Also,
Chamotte is a crushed tile (14 mesh under) made by firing clay of 30 parts by weight of feldspar, 50 parts by weight of clay, and 20 parts by weight of chinastone.

Table 1 Example 2 Example 1 except that the clay composition of the first layer was as shown in Table 2.
A three-layer tile was produced in the same manner. According to this example, the first layer was a pure white layer with a sense of transparency, and was extremely aesthetically pleasing.

Table 2 Example 3 Example 1 except that the clay composition of the first layer was as shown in Table 3.
A three-layer tile was produced in the same manner.

The spots used in this example are made by adding pigment to 50 parts by weight of feldspar, 20 parts by weight of chinastone, and 20 parts by weight of clay, making a slurry, pressing, drying, and crushing (6 mesh under). It is something.

According to this example, a tile having a granite-like surface was obtained.

[Effects] As detailed above, the three-layer tile of the present invention is a laminated tile of three layers, first to third, and the first and third layers have similar shrinkage rates. Therefore, even if there is a considerable difference between the shrinkage rate of the second layer and the shrinkage rates of the first and third layers, the tile will not warp. Following,
Any clay such as industrial waste can be used as the second layer, which is extremely advantageous. Such a three-layer tile of the present invention has the following advantages: (1) low pigment consumption; (2) low-quality materials can be used; (2) adhesion prevention during firing;
This method maintains the advantage of two-layer tiles in that even non-plastic materials can be molded, while solving the problem of warping, which is a disadvantage of two-layer tiles, and is extremely useful industrially. Note that a thermally conductive material, a heat insulating material, or the like may be interposed as the second layer to provide a unique function. Furthermore, since the third layer of the tile of the present invention has a high softening initiation temperature, by firing the third layer with the third layer as the lower surface, explosion adhesion to a refractory for firing such as the roller of a roller hearth kiln is prevented.

Therefore, such a three-layer tile can be manufactured very easily by the method of the present invention, and product defects due to warpage will not occur even in the manufacture of large tiles.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing a three-layer tile of the present invention. Second
Figures (a) to (f) are diagrams for explaining the conventional single-layer molding method, in which (a) to (C) are cross-sectional views, and (d) to (f) are plan views. Figures 3 (a) to (j) are diagrams explaining the conventional two-layer molding method, (a) to (e) are cross-sectional views, and (f) to (
j) is a plan view. FIGS. 4(a) to 4(n) are diagrams explaining the method for manufacturing a three-layer tile of the present invention, and FIGS.
g) is a cross-sectional view, and (h) to (n) are plan views. 1... Upper mold, 2... Lower mold, 3.4.5
... clay container, 3a, 4a, 5a... clay, 10... three-layer tile. Patent Applicant Inax Co., Ltd. Representative Director Teruzo Ina Agent Patent Attorney Tsuyoshi Shigeno Figure 2 Figure 3 Figure 3 Figure 4 Figure 4 Figure 4 (m)

Claims (3)

[Claims] (1) It has a three-layer structure in which the first layer, second layer, and third layer are laminated in this order. A three-layer tile characterized in that the coefficients of thermal expansion are approximately similar, and the third layer contains high refractory grains. (2) The three-layer tile according to claim 1, wherein the first layer includes low refractory grains. (3) Fill the tile mold with raw clay for tiles to form the third layer, fill the third layer with clay different from the clay of the third layer to form the second layer, and then The shrinkage rate during drying and firing and the coefficient of thermal expansion of the sintered base material are approximately similar to those of the third layer clay, and the clay containing high refractory grains is filled on top of the second layer. A method for producing a three-layer tile, characterized by forming a single layer, dry press forming the tile, and then firing it.